<template>
  <div>
    cart-test组件 计数器：{{ count }}
    <button @click="updateCount">+1</button>
  </div>
</template>

<script>
export default {
  name: "CartTest",
  props: {
    count: {
      type: Number,
    },
  },
  emits: ["update:count"],
  setup(props, { emit }) {
    console.log(props.count);
    const updateCount = () => {
      // 通知父组件，让父组件去修改
      emit("update:count", props.count + 1);
    };
    return { updateCount };
  },
};
</script>
